Recently, a mobile information processing apparatus equipped with a touch panel device is used, and especially, in the field of a cellular phone, a touch-panel smart phone which is represented by iPhone (registered trademark) by Apple Inc. is sold increasingly.
Hereinafter, “a mobile information processing apparatus equipped with a touch panel device” is referred as “a touch-panel mobile information processing apparatus”.
In the case of a touch-panel mobile information processing apparatus, a suitable input interface for each application can be realized, since an input screen display of a touch panel can be changed variously by a software. For example, in the case of a touch-panel smart phone, a user can carry out a data input operation on a suitable input screen for each input operation such as a telephone number input for a telephone call, a character input for sending an E-mail, and, more over, a data input for operating various application software containing a game program, and, as a result, the convenience of data input is much more improved than a cellular phone only with a hard key.    Patent Document 1: Japanese laid-open patent publication No. 2008-141519    Patent Document 1: Japanese laid-open patent publication No. 2010-003307
By the way, in the case of a touch-panel mobile information processing apparatus, it is usual that a touch-panel screen is divided into a input area and a display area, and data is inputted by manual operation such as touch or push of the input area and shield of light incoming on the input area, when the input contents are intricately and abundant in such a case as inputting substances.
However, in the case of a mobile information processing apparatus including at least a cellular phone, a smart phone and PDA (Personal Digital Assistant), size and screen resolution (number of level pixels×number of perpendicular pixels) of a attached display cannot be increased in vain, since its portability is thought as important. If, despite of the limitation, the touch-panel screen is divided as mentioned above, the size and displayable pixels of the input area of the screen will become so small that number of keys should be restricted even though, for example, key board for inputting characters (such as letters, numbers and symbols). As a result, in the case of a character input for sending an e-mail, user suffers such inconvenience as to change the display mode of the input area between the case of letter input and the case of number input and to touch the same key repeatedly. For example, in order to input the fifth character of the Japanese syllabary, user is required to push a certain key, which is assigned to first line of the Japanese syllabary (“kana”), five times after changing an input mode to “kana”.
On the other hand, the similar inconvenience occurs also in a display area. Since some part of touch-panel screens, of which size and screen resolution are originally small, is devoted to an input area for data input, contents or image pixels which can be displayed on a display area will be decreased further. For this reason, the problem that the whole text cannot be read without frequent scroll will arise when user polishes the text inputted, for example, on the occasion of text creation of an e-mail.